Bis-alkylbenzylamines

ABSTRACT

Compounds of Formula (1), wherein R 1  is hydrogen; C 1 -C 18 alkyl; trifluoromethyl; C 3 -C 8 cycloalkyl; phenylC 1 -C 5 alkyl; phenyl-C 1 -C 5 alkoxy; mono- or di-N-C 1 -C 5 alkamino-C 1 -C 5 alkyl; amino-di-N-C 1 -C 5 alkylamino-C 1 -C 5 alkyl; C 1 -C 5 alkoxy-C 1 -C 5 alkyl; R 2  is C 2 -C 20 alkyl; hydroxy-C 1 -C 20 alkyl; phenyl; phenyl-C 1- C 5 alkyl; phenyl-C 1 -C 5 alkoxy; mono- or di-N-C 1 -C 5 alkylamino-C 1 -C 5 alkyl; amino-di-N-C 1 -C 5 alkylamino-C 1 -C 5 alkyl; or heteroaryl-C 1 -C 5 alkyl; or R 1  and R 2  together with the nitrogen atom bonding them form a 5- to 7-membered monocyclic heterocyclic ring; are described. They are suitable for the antimicrobial treatment of surfaces, especially as antimicrobial active ingredients against gram-positive and gram-negative bacteria.

The present invention relates to bis-alkylbenzylamines, to thepreparation of those compounds, and to their use in the antimicrobialtreatment of surfaces, as antimicrobial active ingredients againstgram-positive and gram-negative bacteria, yeasts and fungi, and in thepreservation of cosmetics, household products, textiles, plastics, andfor use in disinfectants.

The bis-alkylbenzylamines according to the invention correspond toformula

wherein

-   R₁ is hydrogen; C₁-C₁₈alkyl; trifluoromethyl; C₃-C₈cycloalkyl;    phenyl-C₁-C₅alkyl; phenyl-C₁-C₅alkoxy; mono- or    di-N-C₁-C₅alkylamino-C₁-C₅alkyl; amino-mono- or    di-N-C₁-C₅alkylamino-C₁-C₅alkyl; C₁-C₅alkoxy-C₁-C₅alkyl;-   R₂ is C₂-C₂₀alkyl; hydroxy-C₁-C₂₀alkyl; phenyl; phenyl-C₁-C₅alkyl;    phenyl-C₁-C₅alkoxy; mono- or di-N-C₁-C₅alkylamino-C₁-C₅alkyl;    amino-mono- or di-N-C₁-C₅alkylamino-C₁-C₅alkyl; or    heteroaryl-C₁-C₅alkyl; or-   R₁ and R₂ together with the nitrogen atom bonding them form a 5- to    7-membered mono-cyclic heterocyclic ring;    with the proviso that compounds of formula (1) are excluded wherein-   a. R₁ is hydrogen; and    -   R₂ is butyl;-   b. R₁ is hydrogen; and    -   R₂ is cyclohexyl;-   c. R₁ and R₂ are butyl;-   d. R₁ and R₂ are propyl;-   e. R₁ and R₂ together form a monocyclic ring of the formula-   f. R₁ and R₂ together form a monocyclic ring of the formula-   g. R₁ and R₂ together form a monocyclic ring of the formula

C₁-C₂₀Alkyl are straight-chain or branched alkyl radicals, for examplemethyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl,amyl, isoamyl or tert-amyl, heptyl, octyl, isooctyl, nonyl, decyl,undecyl, dodecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl,octadecyl or eicosyl.

C₃-C₈Cycloalkyl is, for example, cyclopropyl, cyclobutyl, cyclopentyl,cyclohexyl, cycloheptyl or cyclooctyl. Those radicals can besubstituted, e.g. by one or more identical or different C₁-C₄alkylradicals, especially by methyl, and/or by hydroxy. When cycloalkylradicals are substituted by one or more substituents, they arepreferably substituted by one, two or four, especially by one or two,identical or different substituents.

C₁-C₅Alkoxy are straight-chain or branched radicals, for examplemethoxy, ethoxy, propoxy, butoxy or pentyloxy.

Heteroaryl radicals can be unsubstituted or carry one or more, e.g. one,two, three or four, identical or different substituents, which may belocated in any positions. Examples of such substituents are e.g.C₁-C₄alkyl, halogen, hydroxy, C₁-C₄alkoxy, trifluoromethyl, cyano,hydroxycarbonyl, C₁-C₄alkoxycarbonyl, aminocarbonyl, amino,C₁-C₄alkylamino, di-C₁-C₄-alkylamino and C₁-C₄alkylcarbonylamino.

Heteroaryl radicals are derived from heterocycles having one, two, threeor four identical or different ring hetero atoms, especially fromheterocycles having one, two or three, especially one or two, identicalor different hetero atoms. The heterocycles can be mono- or poly-cyclic,e.g. mono-, bi- or tri-cyclic. They are preferably mono- or bi-cyclic,especially mono-cyclic. The rings preferably contain 5, 6 or 7 ringmembers. Examples of monocyclic and bicyclic heterocyclic systems fromwhich radicals appearing in the compounds of formula (1) may be derivedare, for example, pyrrole, furan, thiophene, imidazole, pyrazole,1,2,3-triazole, 1,2,4-triazole, pyridine, pyridazine, pyrimidine,pyrazine, pyran, thiopyran, 1,4-dioxane, 1,2-oxazine, 1,3-oxazine,1,4-oxazine, indole, benzothiophene, benzofuran, pyrrolidine,piperidine, piperazine, morpholine and thiomorpholine.

Unsaturated heterocycles can contain, for example, one, two or threeunsaturated double bonds in the ring system. 5-Membered rings and6-membered rings in monocyclic and polycyclic heterocycles mayespecially also be aromatic.

Preference is given to alkylbenzylamines of formula (1) wherein

-   R₁ is hydrogen; C₁-C₁₈alkyl; trifluoromethyl; C₃-C₈cycloalkyl;    phenyl-C₁-C₅alkyl; phenyl-C₁-C₅alkoxy; mono- or    di-N-C₁-C₅alkylamino-C₁-C₅alkyl;    amino-di-N-C₁-C₅alkylamino-C₁-C₅alkyl; C₁-C₅alkoxy-C₁-C₅alkyl;-   R₂ is C₅-C₂₀alkyl; hydroxy-C₁-C₂₀alkyl; phenyl; phenyl-C₁-C₅alkyl;    phenyl-C₁-C₅alkoxy; mono- or di-N-C₁-C₅alkylamino-C₁-C₅alkyl;    amino-di-N-C₁-C₅alkylamino-C₁-C₅alkyl; or heteroaryl-C₁-C₅alkyl; or-   R₁ and R₂ together with the nitrogen atom bonding them form a 6- or    7-membered mono-cyclic heterocyclic aromatic ring.

Special preference is given to compounds of formula (1) wherein

-   R₁ is hydrogen; C₁-C₈alkyl; benzyl; or together with R₂ forms a 5-    to 7-membered monocyclic heterocyclic ring; and more especially    hydrogen.-   R₂ in formula (1) is preferably C₂-C₁₂alkyl; phenyl-C₁-C₂alkyl;    hydroxy-C₁-C₅alkyl; heteroaryl-C₁-C₂alkyl; or R₂ forms together with    R₁ a 5- to 7-membered monocyclic heterocyclic ring.

Special preference is given to compounds of formula (1) wherein

-   R₂ is a branched C₃-C₈alkyl radical, especially an isopropyl;    isobutyl, tert-butyl; isohexyl; or isooctyl radical.

Special preference is given to compounds of formula (1) wherein R₁ andR₂ have the same meanings.

Of those compounds, preference is given to those wherein

-   R₁ and R₂ are linear C₂-C₁₂alkyl; or benzyl.

Special preference is given to compounds of formula (1) wherein

-   R₁ is hydrogen; or methyl; and-   R₂ is C₂-C₁₂alkyl; or phenyl-C₁-C₂alkyl,    and more especially to compounds of formula (1) wherein-   R₁ is hydrogen.

Very special preference is given to compounds of formula (1) wherein

-   R₁ is hydrogen; and-   R₂ is octyl.

The preparation of the compounds according to the invention is carriedout by processes known per se in accordance with the following scheme:

wherein R₁ and R₂ are as defined for formula (1).

The 4,4′-biphenyl carboxaldehyde is reacted with from 1 to 3 equivalentsof amine and a reducing agent, e.g. hydrogen and a metal catalyst,formic acid, metal hydrides, e.g. borane complexes, borohydrides,aluminium hydrides, etc., in a suitable solvent, e.g. THF, DMF, dioxane,toluene, xylene, methanol or ethanol, with or without acid catalysis(acetic acid, TMOF) at a temperature of from −10° C. to 150° C. in thecourse of from 1 to 24 h, to form the corresponding amine compound.

In a further preparation variant, the bis-alkylbenzylamines according tothe invention can be prepared in only one reaction step by directalkylamination of BCMD. The process, which is a further subject of theinvention, can be carried out as follows:

The alkylamination of BCMD is generally carried out in an excess ofR₁—NH₂. The solvent (toluene) and the excess of R, —NH₂ can be recycledby distillation. The reaction time is from 0.5 to 12, preferably from 1to 3 hours. The reaction temperature is from 50 to 120, preferably from70 to 90° C.

Preferred solvents are toluene, xylene or fractions from petrol.

Examples of compounds according to the invention are listed in Table 1:Compound Purity of formula Structure [254nm] 2

58 3

60 4

87 5

72 6

82 7

67 8

54 9

83 10

85 11

80 12

87 13

90 14

76 15

68 16

82 17

84 18

53 19

92 20

80 21

75 22

83 23

65 24

54 25

76 26

60 27

53 28

45 29

68 30

73 31

53

The bis-alkylbenzylamines used according to the invention exhibit apronounced antimicrobial action, especially against pathogenicgram-positive and gram-negative bacteria and also against bacteria ofskin flora. They are therefore especially suitable for the disinfection,deodorisation and the general and antimicrobial treatment of the skinand mucosa and also of integumentary appendages (hair), more especiallyfor the disinfection of the hands and of wounds. They are thereforesuitable as antimicrobial active ingredients and preservatives inpersonal care preparations, for example shampoos, bath additives,hair-care products, liquid and solid soaps (based on syntheticsurfactants and salts of saturated and/or unsaturated fatty acids),lotions and creams, deodorants, other aqueous or alcoholic solutions,e.g. cleansing solutions for the skin, moist cleansing cloths, oils orpowders.

The invention therefore relates also to a personal care preparationcomprising at least one compound of formula (1) as well as cosmeticallytolerable carriers or adjuvants.

The personal care preparation according to the invention comprises from0.01 to 15% by weight, preferably from 0.1 to 10% by weight, based onthe total weight of the composition, of bis-alkylbenzylamines of formula(1), and cosmetically tolerable adjuvants.

Depending upon the form of the personal care preparation, it comprises,in addition to the bis-alkylbenzylamine compound of formula (1), furtherconstituents, for example sequestering agents, colourings, perfume oils,thickening or solidifying agents (consistency regulators), emollients,UV absorbers, skin-protective agents, antioxidants, additives thatimprove mechanical properties, such as dicarboxylic acids and/or Al, Zn,Ca and Mg salts of C₁₄-C₂₂-fatty acids, and optionally preservatives.

The personal care preparation according to the invention may beformulated as a water-in-oil or oil-in-water emulsion, as an alcoholicor alcohol-containing formulation, as a vesicular dispersion of an ionicor non-ionic amphiphilic lipid, as a gel, a solid stick or as an aerosolformulation.

As a water-in-oil or oil-in-water emulsion, the cosmetically tolerableadjuvant contains preferably from 5 to 50% of an oily phase, from 5 to20% of an emulsifier and from 30 to 90% water. The oily phase maycontain any oil suitable for cosmetic formulations, e.g. one or morehydrocarbon oils, a wax, a natural oil, a silicone oil, a fatty acidester or a fatty alcohol. Preferred mono- or poly-ols are ethanol,isopropanol, propylene glycol, hexylene glycol, glycerol and sorbitol.

Cosmetic formulations according to the invention are used in a varietyof fields. Especially the following preparations, for example, come intoconsideration:

-   -   skin-care preparations, e.g. skin-washing and cleansing        preparations in the form of tablet-form or liquid soaps,        synthetic detergents or washing pastes;    -   bath preparations, e.g. liquid (foam baths, milks, shower        preparations) or solid bath preparations, e.g. bath cubes and        bath salts;    -   skin-care preparations, e.g. skin emulsions, multi-emulsions or        skin oils;    -   cosmetic personal care preparations, e.g. facial make-up in the        form of day creams or powder creams, face powder (loose or        pressed), rouge or cream make-up, eye-care preparations, e.g.        eyeshadow preparations, mascara, eyeliner, eye creams or eye-fix        creams; lip-care preparations, e.g. lipsticks, lip gloss, lip        contour pencils, nail-care prep-arations, such as nail varnish,        nail varnish removers, nail hardeners or cuticle removers;    -   intimate hygiene preparations, e.g. intimate washing lotions or        intimate sprays;    -   foot-care preparations, e.g. foot baths, foot powders, foot        creams or foot balsams, special deodorants and antiperspirants        or callus-removing preparations;    -   light-protective preparations, such as sun milks, lotions,        creams and oils, sun blocks or tropicals, pre-tanning        preparations or after-sun preparations; skin-tanning        preparations, e.g. self-tanning creams;    -   depigmenting preparations, e.g. preparations for bleaching the        skin or skin-lightening preparations;    -   insect-repellents, e.g. insect-repellent oils, lotions, sprays        or sticks; deodorants, such as deodorant sprays, pump-action        sprays, deodorant gels, sticks or roll-ons;    -   antiperspirants, e.g. antiperspirant sticks, creams or roll-ons;    -   preparations for cleansing and caring for blemished skin, e.g.        synthetic detergents (solid or liquid), peeling or scrub        preparations or peeling masks;    -   hair-removal preparations in chemical form (depilation), e.g.        hair-removing powders, liquid hair-removing preparations, cream-        or paste-form hair-removing preparations, hair-removing        preparations in gel form or aerosol foams;    -   shaving preparations, e.g. shaving soap, foaming shaving creams,        non-foaming shaving creams, foams and gels, preshave        preparations for dry shaving, aftershaves or aftershave lotions;    -   fragrance preparations, e.g. fragrances (eau de Cologne, eau de        toilette, eau de parfum, parfum de toilette, perfume), perfume        oils or cream perfumes;    -   dental-care, denture-care and mouth-care preparations, e.g.        toothpastes, gel tooth-pastes, tooth powders, mouthwash        concentrates, anti-plaque mouthwashes, denture cleaners or        denture fixatives;    -   cosmetic hair-treatment preparations, e.g. hair-washing        preparations in the form of shampoos, hair conditioners,        hair-care preparations, e.g. pretreatment preparations, hair        tonics, styling creams, styling gels, pomades, hair rinses,        treatment packs, intensive hair treatments, hair-structuring        preparations, e.g. hair-waving preparations for permanent waves        (hot wave, mild wave, cold wave), hair-straightening        preparations, liquid hair-setting preparations, foams,        hairsprays, bleaching preparations, e.g. hydrogen peroxide        solutions, lightening shampoos, bleaching creams, bleaching        powders, bleaching pastes or oils, temporary, semi-permanent or        permanent hair colorants, preparations containing self-oxidising        dyes, or natural hair colorants, such as henna or camomile.

An antimicrobial soap has, for example, the following composition: 0.01to 5% by weight of a compound of formula (1) 0.3 to 1% by weighttitanium dioxide 1 to 10% by weight stearic acid ad 100% soap base, e.g.the sodium salts of tallow fatty acid and coconut fatty acid orglycerol.

A shampoo has, for example, the following composition: 0.01 to 5% byweight of a compound of formula (1) 12.0% by weight sodiumlaureth-2-sulfate 4.0% by weight cocamidopropyl betaine 3.0% by weightNaCl and ad 100% water.

A deodorant has, for example, the following composition: 0.01 to 5% byweight of a compound of formula (1) 60% by weight ethanol 0.3% by weightperfume oil and ad 100% water.

The invention relates also to an oral composition, comprising from 0.01to 15% by weight, based on the total weight of the composition, of acompound of formula (1), and orally tolerable adjuvants.

Example of an oral composition: 10% by weight sorbitol 10% by weightglycerol 15% by weight ethanol 15% by weight propylene glycol 0.5% byweight sodium lauryl sulfate 0.25% by weight sodium methylcocyl taurate0.25% by weight polyoxypropylene/polyoxyethylene block copolymer 0.10%by weight peppermint flavouring 0.1 to 0.5% by weight of a compound offormula (1) and 48.6% by weight water.

The oral composition according to the invention may be, for example, inthe form of a gel, a paste, a cream or an aqueous preparation(mouthwash).

The oral composition according to the invention may also comprisecompounds that release fluoride ions which are effective against theformation of caries, for example inorganic fluoride salts, e.g. sodium,potassium, ammonium or calcium fluoride, or organic fluoride salts, e.g.amine fluorides, which are known under the trade name Olafluor.

The bis-alkylbenzylamines of formula (1) according to the invention arealso suitable for the treatment, especially the preservation, of textilefibre materials. Such materials are undyed and dyed or printed fibrematerials, e.g. of silk, wool, polyamide or polyurethanes, andespecially cellulosic fibre materials of all kinds. Such fibre materialsare, for example, natural cellulose fibres, such as cotton, linen, juteand hemp, as well as cellulose and regenerated cellulose. Preferredsuitable textile fibre materials are made of cotton.

The bis-alkylbenzylamines according to the invention are also suitablefor the treatment of plastics, especially for imparting antimicrobialproperties to or preserving plastics, e.g. polyethylene, polypropylene,polyurethane, polyester, polyamide, polycarbonate, latex etc. Fields ofuse therefor are, for example, floor coverings, plastics coatings,plastics container and packaging materials; kitchen and bathroomutensils (e.g. brushes, shower curtains; sponges, bathmats), latex,filter materials (air and water filters), plastics articles used in thefield of medicine, e.g. dressing materials, syringes, catheters etc.,so-called “medical devices”, gloves and mattresses.

Paper, for example papers used for hygiene purposes, may also beprovided with anti-microbial properties using the bis-alkylbenzylaminesaccording to the invention.

It is also possible for nonwovens, e.g. nappies/diapers, sanitarytowels, panty liners, and cloths for hygiene and household uses, to beprovided with antimicrobial properties according to the invention.

The bis-alkylbenzylamines of formula (1) are also used in washing andcleaning formulations, e.g. in liquid and powder washing agents or insofteners.

The bis-alkylbenzylamines can be used especially also in household andall-purpose cleaners for cleaning and disinfecting hard surfaces. Acleaning preparation has, for example, the following composition: 0.01to 5% of a compound of formula (1) 3.0% octyl alcohol 4EO 1.3% fattyalcohol C₈-C₁₀polyglucoside 3.0% isopropanol ad 100% water.

Also possible, in addition to the preservation of cosmetic and householdproducts, is the preservation of technical products and the provision ofsuch products with antimicrobial properties as well as use as a biocidein technical processes, such as in paper treatment, especially in papertreatment liquors, printing thickeners of starch or of cellulosederivatives, surface-coatings and paints.

The bis-alkylbenzylamines of formula (1) are also suitable for theantimicrobial treatment of wood and for the antimicrobial treatment ofleather, the antimicrobial preservation of leather and the provision ofleather with antimicrobial properties.

The compounds according to the invention are also suitable for theprotection of cosmetic products and household products from microbialspoilage.

The following Examples serve to illustrate the invention but do notlimit the invention.

EXAMPLES Example 1 Preparation ofoctyl-(4′-octylaminomethyl-biphenyl-4-ylmethyl)-amine (Compound ofFormula (3))

4.20 g (20 mmol) of 4,4′-biphenyl dicarboxaldehyde are dissolved in 50ml of absolute THF under nitrogen. 4.80 g (80 mmol) of acetic acid and5.69 g (44 mmol) of octylamine are added dropwise thereto and themixture is heated for 1 hour at 60° C. After cooling with an ice-bath,10.17 g (48 mmol) of sodium triacetoxyborohydride are added in portions.The reaction mixture is stirred overnight at room temperature. 100 ml ofwater are placed in a container and the reaction mixture is added usinga pipette. The pH is adjusted to 1 with 6N hydrochloric acid. The THF isdistilled off, and the product is filtered off and washed with 900 ml ofwater.

The product is then suspended in ethyl acetate, adjusted to pH 13 withsodium hydroxide solution and then filtered off again.

The product is washed with 300 ml of water. Excess octylamine isdistilled off under a high vacuum.

Yield: 84% (GC purity: 88%)

NMR (methanol): 0.8 ppm (6H); 1.2 ppm (20H); 1.45 ppm (4H); 2.5 ppm(4H); 3.7 ppm (4H); 7.3 ppm (4H); 7.5 ppm (4H)

Example 2 Preparation ofoctyl-(4′-octylaminomethyl-biphenyl-4-ylmethyl)-amine (compound offormula (3))

A suspension of BCMD (1.00 mol) in toluene (2600 ml) is treated whilecold with an excess of n-octylamine (5.00 mol). After reaction for onehour at 80° C., the conversion is complete. The reaction suspension iswashed out with water (1000 ml) and 50% NaOH (200 g). The solvents(toluene/n-octylamine) are distilled off in vacuo (60-120° C./20 mbar).

The oily residue is taken up in warm ethyl acetate (1200 ml), clarifiedon a suction-filter (BCMD polymer), cooled to 35° C. and seeded.

After further cooling to 0° C., the crystalline product is filtered off,washed with solvent and dried.

Example 3 Determination of the Minimum Inhibiting Concentration (MICValue) in Microtitre Plates

Nutrient Medium:

Casein/soybean flour peptone bouillon for the preparation of theprecultures of the test bacteria and yeast.

Examples of Test Organisms:

Bacteria: Escherichia coli ATCC 10536 (=EC) Staphylococcus aureus ATCC6538(=SA)

Procedure:

The test substances are predissolved in dimethyl sulfoxide (DMSO) andtested in a serial dilution of 1:2.

Bacteria and yeast are cultured overnight in CASO bouillon.

All test organism suspensions are adjusted to an organism count of1-5×10⁶ CFU/ml with 0.85% sodium chloride solution.

The test substances are prepipetted into microtitre plates in an amountof 8 μl per well. The previously adjusted organism suspensions arediluted 1:100 in CASO bouillon and added to the test substances in anamount of 192 μl per well.

The test batches are incubated for 48 hours at 37° C.

After incubation, the growth is determined by reference to the turbidityof the test batches (optical density) at 620 nm in a microplate reader.

The minimum inhibiting concentration (MIC value) is the concentration ofsubstance at which an appreciable inhibition of the growth (<20% growthcompared with the growth control) of the test organisms is ascertained.

Three microtitre plates are used for each test organism and substanceconcentration.

The microbiological test results are compiled in Table 2: TABLE 2 PurityCompound of formula [254 nm] ATCC 6538 ATCC 10536 2 58 15 15 3 60 7.5<3.75 4 87 30 15 5 72 30 30 6 82 30 30 7 67 15 30 8 54 15 60 9 8360 >120 10 85 15 30 11 80 30 30 12 87 30 60 13 90 7.5 7.5 14 76 30 >12015 68 120 120 16 82 60 120 17 84 15 15 18 53 >120 >120 19 92 >120 >12020 80 >120 >120 21 75 >120 120 22 83 15 15 23 65 15 >120 24 54 >120 >12025 76 >120 >120 26 60 30 >120 27 53 15 >120 28 45 7.5 15 29 68 >120 >12030 73 >120 >120 31 53 60 120

Example 4 Determination of the Minimum Inhibiting Concentration of theCompound of Formula (3) in Respect of a Wider Spectrum of Organisms

The compound of formula (3) (see Table 1; GC purity 88%; prepared inaccordance with Example 1) is tested on the microorganisms indicated inTable 3.

The test for determining the minimum inhibiting concentration iseffected in an agar incorporation test. TABLE 3 Microorganism MICStaphylococcus aureus ATCC 6538 3.75 Staphylococcus aureus ATCC 91443.75 Staphylococcus epidermidis ATCC 12228 3.75 Corynebacterium xerosisATCC 373 1.88 C. minutissimum ATCC 23348 1.88 Propionibacterium acnesATCC 6919 3.75 Escherichia coli NCTC 8196 3.75 Escherichia coli ATCC10536 3.75 Proteus vulgaris ATCC 6896 >120 Klebsiella pneumoniae ATCC4352 7.5 Salmonella choleraesuis ATCC 9184 7.5 Pseudomonas aeruginosaATCC 15442 >120 Candida albicans ATCC 10231 >120 Aspergillus niger ATCC6275 >120

1. An alkylbenzylamine of formula

wherein R₁ is hydrogen; C₁-C₁₈alkyl; trifluoromethyl; C₃-C₈cycloalkyl;phenyl-C₁-C₅alkyl; phenyl-C₁-C₅alkoxy; mono- ordi-N-C₁-C₅alkylamino-C₁-C₅alkyl; amino-mono- ordi-N-C₁-C₅alkylamino-C₁-C₅alkyl; or C₁-C₅alkoxy-C₁-C₅alkyl; R₂ isC₂-C₂₀alkyl; hydroxy-C₁-C₂₀alkyl; phenyl; phenyl-C₁-C₅alkyl;phenyl-C₁-C₅alkoxy; mono- or di-N-C₁-C₅alkylamino-C₁-C₅alkyl;amino-mono- or -di-N-C₁-C₅alkylamino-C₁-C₅alkyl; orheteroaryl-C₁-C₅alkyl; or R₁ and R₂ together with the nitrogen atombonding them form a 5- to 7-membered monocyclic heterocyclic ring; withthe proviso that compounds of formula (1) are excluded wherein a. R₁ ishydrogen; and R₂ is butyl; b. R₁ is hydrogen; and R₂ is cyclohexyl; c.R₁ and R₂ are butyl; d. R₁ and R₂ are propyl; e. R₁ and R₂ together forma monocyclic ring of the formula

f. R₁ and R₂ together form a monocyclic ring of the formula

g. R₁ and R₂ together form a monocyclic ring of the formula


2. An alkylbenzylamine of formula

wherein R₁ is hydrogen; C₁-C₁₈alkyl; trifluoromethyl; C₃-C₈cycloalkyl;phenyl-C₁-C₅alkyl; phenyl-C₁-C₅alkoxy; mono- ordi-N-C₁-C₅alkylamino-C₁-C₅alkyl; amino-di-N-C₁-C₅alkylamino-C₁-C₅alkyl;or C₁-C₅alkoxy-C₁-C₅alkyl; R₂ is C₅-C₂₀alkyl; hydroxy-C₁-C₂₀alkyl;phenyl; phenyl-C₁-C₅alkyl; phenyl-C₁-C₅alkoxy; mono- ordi-N-C₁-C₅alkylamino-C₁-C₅alkyl; amino-di-N-C₁-C₅alkylamino-C₁-C₅alkyl;or heteroaryl-C₁-C₅alkyl; or R₁ and R₂ together with the nitrogen atombonding them form a 6- or 7-membered monocyclic heterocyclic aromaticring.
 3. A compound according to claim 1, wherein R₁ is hydrogen;C₁-C₈alkyl; benzyl; or together with R₂ forms a 5- to 7-memberedmonocyclic heterocyclic ring.
 4. A compound according to claim 1,wherein R₁ is hydrogen.
 5. A compound according to claim 1, wherein R₂is C₂-C₁₂alkyl; phenyl-C₁-C₂alkyl; hydroxy-C₁-C₅alkyl;heteroaryl-C₁-C₂alkyl; or together with R₁ forms a 5- to 7-memberedmonocyclic heterocyclic ring.
 6. A compound according to claim 1,wherein R₂ is a branched C₃-C₈alkyl radical.
 7. A compound according toclaim 6, wherein R₂ is an isopropyl; isobutyl, tert-butyl; isohexyl; orisooctyl radical.
 8. A compound according to claim 5, wherein R₁ ishydrogen; and R₂ is octyl.
 9. A compound according to claim 1, whereinR₁ and R₂ have the same meanings.
 10. A compound according to claim 9,wherein R₁ and R₂ are linear C₂-C₁₂alkyl; or benzyl.
 11. A compoundaccording to claim 1, wherein R₁ is hydrogen; or methyl; and R₂ isC₂-C₁₂alkyl; or phenyl-C₁-C₂alkyl.
 12. (canceled)
 13. A method ofantimicrobial treatment of a surface, which comprises contacting saidsurface with an antimicrobially effective amount of a compound offormula (1) wherein R₁ is hydrogen; C₁-C₁₈alkyl; trifluoromethyl;C₃-C₈cycloalkyl; phenyl-C₁-C₅alkyl; phenyl-C₁-C₅alkoxy; mono- ordi-N-C₁-C₅alkylamino-C₁-C₅alkyl; amino-di-N-C₁-C₅alkylamino-C₁-C₅alkyl;or C₁-C₅alkoxy-C₁-C₅alkyl; R₂ is C₂-C₂₀alkyl; hydroxy-C₁-C₂₀alkyl;phenyl; phenyl-C₁-C₅alkyl; phenyl-C₁-C₅alkoxy; mono- ordi-N-C₁-C₅alkylamino-C₁-C₅alkyl; amino-di-N-C₁-C₅alkylamino-C₁-C₅alkyl;or heteroaryl-C₁-C₅alkyl; or R₁ and R₂ together with the nitrogen atombonding them form a 5- to 7-membered monocyclic heterocyclic ring.
 14. Amethod according to claim 13, wherein the compound is used in thedeodorisation and disinfection of the skin, mucosa or hair.
 15. A methodaccording to claim 13, wherein the compound is used in the treatment oftextile fibre materials.
 16. A method according to claim 13, wherein thecompound is used in the preservation and antimicrobial treatment oftechnical products.
 17. A method according to claim 16, wherein thetechnical product is a plastic, paper, nonwovens, wood or leather.
 18. Amethod according to claim 13, wherein the compound is used as anantimicrobial active ingredient in washing and cleaning formulations.19. (canceled)
 20. A personal care preparation, comprising from 0.01 to15% by weight, based on the total weight of the composition, of acompound of formula (1) according to claim 1, and cosmetically tolerableadjuvants.
 21. An oral composition, comprising from 0.01 to 15% byweight, based on the total weight of the composition, of a compound offormula (1) according to claim 1, and orally tolerable adjuvants.
 22. Aprocess for the preparation of a compound of formula (1) according toclaim 1, wherein it is prepared in accordance with the following scheme:

wherein R₁ and R₂ are as defined in claim
 1. 23. A process for thepreparation of a compound of formula (1) according to claim 1, whereinit is prepared in accordance with the following scheme:

wherein R₁ is as defined in claim 1.